Yosemite National Park continues its public health response and outreach as a result of confirmed cases of hantavirus pulmonary syndrome (HPS) in individuals who spent one or more nights in the park between June 10 and late August of this year in the “Signature Tent Cabins” located in Curry Village. The National Park Service Office of Public Health is working with the Centers for Disease Control and Prevention (CDC) and state public health offices to heighten public health awareness and detection of the disease.

“We want to make sure that visitors have clear information about this rare virus and understand the importance of early medical care,” said Yosemite Superintendent Don Neubacher. “We continue to work closely with state and national public health officials, and we urge visitors who may have been exposed to hantavirus to seek medical attention at the first sign of symptoms.”

The National Park Service has received confirmations from national and state public health agencies of HPS cases linked to eight individuals who stayed one night or more in Yosemite since June of this year. Three cases have resulted in fatality; the five remaining individuals are either improving or recovering. The confirmed cases include six individuals from California, one from Pennsylvania, and one from West Virginia. The types of hantavirus that cause HPS in the United States cannot be transmitted from one person to another.

Seven of the eight cases of HPS have been linked to the “Signature Tent Cabins” in Curry Village in Yosemite Valley. Those cabins have been closed and parties who stayed overnight since June 10 have been reached out to by the park or the operator of Curry Village, DNC Parks & Resorts at Yosemite, Inc.

The California Department of Public Health (CDPH) has advised the National Park Service that one of the eight confirmed cases of HPS stayed in multiple High Sierra Camps in Yosemite (a different area of the park than Curry Village) in July, and that the stay in the High Sierra Camps is the most likely source of that person’s infection. This individual exhibited mild symptoms and is recovering.

In order to increase public awareness and detection of this rare disease, the park is providing information regarding HPS risks and symptoms to parties who made reservations at the High Sierra Camps this summer and parties who are registered to stay before the camps close for the season on September 17.

The park is distributing hantavirus information to every visitor entering Yosemite and notices are posted throughout the park. In addition, a call center has been established for questions and concerns related to hantavirus in Yosemite (209) 372-0822. The phones are staffed from 9:00 a.m. to 5:00 p.m. daily.

HPS is a rare but serious disease that occurs throughout the United States and is caused by a virus that individuals get through contact with the urine, droppings or saliva of infected rodents. Since HPS was first identified in 1993, there have been approximately 60 cases in California and 602 cases nationally. Nationwide, approximately 20 percent of mice carry hantavirus.

According to the CDC, symptoms of HPS generally begin from one to five weeks after exposure. Early symptoms include fatigue, fever, chills, and muscle aches. About half of patients will experience headaches, nausea, vomiting, dizziness and abdominal pain. The disease progresses rapidly (4-10 days after initial symptoms) to include coughing, shortness of breath and severe difficulty breathing. Early medical attention greatly increases the chance of survival in cases of HPS. It is recommended that if a recent visitor to Yosemite National Park has any of the symptoms listed above, that they seek medical attention immediately and advise their health care professional of the potential exposure to hantavirus.

DNC said that they are down occupancy by 20%. We know someone that has a B&B in the area and they are getting cancellations. We have been to Yosemite 4 times since Memorial Day Weekend and were surprise that is was not as crowded as usual. The media kept talking about the Carrying Capacity and how bad the traffic is and that probably made some people not come, the economy is bad and now there is the hantavirus. I really feel bad for people in the surrounding areas that depend on the tourists because they are loosing money and you wonder how many will go out of business.

I have a friend who is going with his family next week and one of the family members is worried that they will get sick. They are not staying in the park but the family member thinks that they will get the virus if they just go into the valley and walk around. I have been trying to assure them that the chances of that happening is extremely rare. She insists on bringing bottles of hand disinfectant dispite the fact that inhaling dried urine and feces is the most common way of catching it. Well, at least she will not catch a cold or flu from having dirty hands.

DNC said that they are down occupancy by 20%. We know someone that has a B&B in the area and they are getting cancellations. We have been to Yosemite 4 times since Memorial Day Weekend and were surprise that is was not as crowded as usual. The media kept talking about the Carrying Capacity and how bad the traffic is and that probably made some people not come, the economy is bad and now there is the hantavirus. I really feel bad for people in the surrounding areas that depend on the tourists because they are loosing money and you wonder how many will go out of business.

Visitation has been down in Yosemite the whole spring and summer, even before that hantavirus outbreak hit the news.

I think the main reason for the drop is because so many people visited Yosemite last summer coupled with everyone knowing that this would be a very dry summer (read less spectacular waterfalls), that a good number of people crossed off visiting Yosemite this summer. If the snowpack is back to at least normal next spring, I'm sure that visitation to Yosemite will pick up (unless visitors keep on getting infected with the hantavirus throughout fall and winter).

I agree with plawrence about Yosemite visitation...the masses came last year with the much publicized high runoff. Not only would the waterfalls be less spectacular this year, but rafting, an activity that families look forward to in the hot summer season, was severly restricted due to low water conditions. (Our rafters were scraping bottom in early June.)

Notifications about the hantavirus have expanded...recreation.gov has sent out warnings to past campers via email

The hantavirus has probably been present in Yosemite for more than a decade...we have had to deal with it, taking precautions, here on the eastside for at least 15 years.

As part of the effort to locate the source of the virus, researchers located and examined stored samples of lung tissue from people who had died of unexplained lung disease. Some of these samples showed evidence of previous infection with Sin Nombre virus—indicating that the disease had existed before the "first" known outbreak—it simply had not been recognized!

Other early cases of HPS have been discovered by examining samples of tissue belonging to people who had died of unexplained adult respiratory distress syndrome. By this method, the earliest known case of HPS that has been confirmed has been the case of a 38-year-old Utah man in 1959.

Interestingly, while HPS was not known to the epidemiologic and medical communities, there is evidence that it was recognized elsewhere. The Navajo Indians, a number of whom contracted HPS during the 1993 outbreak, recognize a similar disease in their medical traditions, and actually associate its occurrence with mice. As strikingly, Navajo medical beliefs concur with public health recommendations for preventing the disease.

Recently I was talking to a local Native American and he was telling me that the Elders said that during times of high deer mouse populations that if one ran across you or your food that you were to wash immediately and throw that food away. HPS is that old.

So the question in my mind has always been, "Why aren't the cleaning staff, who get a hundred times the exposure of the average tourist, all sick with hantavirus?" And why haven't they all been tested for the tell-tale antibodies?

It appears that someone else has also asked this question. Maybe the crew will finally get tested. Perhaps they all did have it, but being young and fit, they just shrugged it off? If so, this would be the complete opposite of what happened with the great flu of 1917, where the young and healthy had the most severe lung reaction to the virus and had a disproportionately high death rate...

Quotewhereverwho get a hundred times the exposure of the average tourist

Assumes fact not in evidence.

OK. ...who have swept out tent cabins hundreds of times more often than the tourists have, especially since they removed the brooms from those cabins a few years ago. And aren't there still some tent cabins occupied by employees, who stay longer than any tourist would?